A circuit breaker is a safety device used in electrical installations. How does a circuit breaker protect an electrical circuit when the current in it exceeds its safety threshold?
It opens a switch to break the circuit, completely stopping the current.
It increases its internal resistance to scale down the current.
It diverts the excess current to the earth wire.
It lowers the supply voltage to reduce the current.
135 exam-style questions on CIE IGCSE Physics Electrical safety, covering Electrical safety. Each one has a worked solution and a mark scheme showing where the marks go.